Radio signaling and control



Sept. 15, 1925.

c. P. RYAN RADIO SIGNALING AND CONTROL Filed Fab. 2'1, 1924 Patented Sept. 15, 1925.

UNITED STATES PATENTOFFICE.

CYRIL PERCY RYAN, OF EAST MOLESEY, ENGLAND, ASSIGNOR TO VIGKERS LIMITED, OF WESTMINSTER, ENGLAND, A BRITISH COMPANY.

RADIO SIGNALING AND CONTROL;

Application filed February 27, 1924. Serial No. 695,397.

To all whom it may concern: I

Be it known that I, CYRIL PERoY RYAN, a subject of the King of Great Britain, residing at Shotley House, East Molesey, in the county of Surrey, England, have invented certain new and useful Improvements in Radio Signaling and Control, of which the following is a specification.

This invention relates to an improved radio system whereby signals may be transmitted to a receiving station and employed to operate a recorder or any apparatus it is desired to control, the chief object of the invention being to provide a system which will effectively prevent any danger of an outside station ascertaining the nature of the signals and interfering with the operation of the receiver.

In 'the improved system radio controlling impulses are sent from the transmitting station at regularly timed intervals at a prede- "termined acoustic frequency or frequencies to which the receiving apparatus is tuned,

I together with impulses of other acoustic frequencies succeeding or superposed upon the operating impulses or signals to produce an apparently incoherent or confused success'ion of impulses and the radio receiver operates an acoustic transmitter which in its turn operates an acoustic receiver'tuned to respond only to the signaling frequency and controlling, through suitable relaying means, an electric circuit which acts upon an oscillatory inertia member whose natural period of swing is that of the timed impulses and which is adapted to buildup its oscillations of successive impulses until their amplitude reaches a predetermined amount, whereupon the; said member operates an electrical actu ating yeifect.

The accompanying drawings illustrate diagrammatically in Fi ure 1 the complete circuit to produce any ,pre-arranged system, the transmitter eing shown at the left. hand side and the receiving and controlling apparatus at the right, while Figure'2 illustrates a slight modification of the receiving apparatus. The radio apparatus "illustrated in the'diagrams is given merely by Way of example as the arrangement of valves and circuits is of standard type" and may embody any appropriate standard practice.

A is the oscillating inertia member in the -form of a Wheel or disc pivoted at a in a support B and, controlled by the coiled I spring 0 which determines the natural oscillation period of the wheel. The spring is attached atone end to the pivot pin a and at the other to a stud b on the support B, the spring being adjusted to any period desired. D, D are controlling electromagnets, two being shown in the arrangement illus trated, the cores (:3 of which approach the periphery of the wheel A.- The latter is provided with a pair of wedge shaped soft iron pole pieces a at opposite sides of the wheel and adjacent to the electromagnets. The wedge form of the pole pieces a is intended to give a smoother andmore regular action to the wheel when controlled by the electromagnets D, D so that the wheel oscillations steadily build up as successive timed impulses are given. I

The wheel is used to control any desired operation'when a given amplitude has been attained, by, for example, closing an electrical circuit E through a contact arm a on the wheel spindle or pivot pin a and a sta-- tionary contact spring 6.

In the general arrangement of apparatus shown in Figure 1 a tunedantenna circuit F is employed with a valve G in an ordinaryradio receiving circuit and a telephone receiver or sound emitter H of loud speaker type emits the controlling signals as sound vibrations. The transmitting apparatus diagrammatically indicated at the left hand side of Figure 1 comprisesa radio transmitter of ordinary type adapted to send impulses of audio frequency on a carrier wave of high frequency. In the diagram J is the transmitting aerial with tuning inductance y and variable condenser j. K is the oscillating valve having its grid coupled to the tuned inductance j through the coil is. L is a modulating valve operated through the low frequency transfOrmerM, the primaryof which is in the circuit n of the microphone N. O is-the power source, indicated as a dynamo, and a low frequency choking coil P is inserted in the circuit between the modulating valve and the current source and a high frequency choking coil P" inserted between the two valves. To. transmit the controlling signals at the required rate and having the desired acoustic frequency or frequencies (two being emon which rests the usual gramophone needle R, the lever r of which operates the microphone N. The sound record disc is cut with a record giving, when the disc is rotated at the proper speed, a succession of signals at the required acoustic frequency or frequencies to operate the receiving circuit and timed to the natural low frequency period of the oscillating wheel A. Superposed upon these operating signals, are other inoperative or confusing signals impressed upon the record in order and simultaneous with or interposed between the operating signals so that a listener in would find it impossible to detect the controlling system, while the superposed 'or confusing signals have no effect upon the timed receiving system. In the dual control, illustrated by way of example, with two controlling electromagnets D, D, two frequencies would be employed of say, 1,000 and 1,500 per second, the impulses of the two frequencies being alternated.

To excite the two electro-magnets D, D independently of one another by means of the two transmitted frequencies two tuned acoustic receivers S, S are placed adjacent to the sound emitter H, these tuned receivers responding to the two different notes, say 1,000 and 1,500 vibrations per second respectively. The acoustic tuning is effected in any known manner as, for example, by altering the effective length of the receivers S, S by the telescopic tube arrangement shown. Each receiver S, S carries an electrical transmitter s, which may be a microphone in the circuit T which includes the battery t, operating the corresponding local telephone receiver U or U which serves as a relay for the local circuit V or V with batteries '0, '0 controlled through the chattering contacts IV, :W the light almost balk anccd contact arm resting on a reed ubelonging to the receiver U or U. IVhen one of the tuned acoustic receivers S or S receives an impulse of the note to which it is tuned the telephone receiver U or U is affected and the vibration of the oscillating member or reed 11 causes the contact arm WV or IV to jump and by the intermittent breaking of the circuit U or U to alter the current in the electromagnet D or D. In the arrangementshown the magnets D, D are normally excited by the small currentpassing through the local circuit V or V so that they exercise a normal attraction upon the wedge-shaped pole pieces a of the wheel A, while any reduction in the magnetic flux due to the intermittent breaking of the exciting circuit allows the spring C to turn the wheel. By properly timing the operation of the impulses the swing of the wheel increases and the amplitude is built up until the circuit E is closed through the contact a and 6.

The chattering contact relay shown in Figure 1 is, of course, given merely as an example and another method of operating the wheel is indicated in the diagram, Figure 2, where the acoustic receivers S, S operate the microphone circuits T T each havingthe primary t of a transformer, the secondary u of which is in the electromagnet circuit V V which includes a rectifier '0 The receiver impulses acting through the tuned acoustic receivers cause the corresponding electromagnets to be excited intermittently through the rectified current in the local electromagnet circuits, the action of the Wheel being the reverse of that previously described, as the electromagnets are excited at each impulse instead of having their normally acting exciting circuits interrupted,

What I claim and desire to secure by Letters Patent of the United States is 1. In a radio signaling control system, means for emitting a regularly timed succession of operative radio signals each of predetermined acoustic frequency, together with signaling impulses of other acoustic frequencies, tuned receiving apparatus adapted to respond only to the said operative radio signals and oscillatory mechanism operated through the said receiving apparatus and having an oscillation period corresponding to the said timed succession of impulses.

2. In a radio signaling control system, means for automatically operating radio transmitting apparatus to send a regularly timed succession of operative radio signals each of predetermined acoustic fre uency, together with signaling impulses 0 other acoustic frequencies, tuned receiving apparatus adapted to respond only to the said operative radio signals and oscillatory mechanism operated through the said receiving apparatus and having an oscillation period corresponding to the said timed succession of impulses.

3. In a radio signaling system, a single sound recording member having impressed upon it a succession of signals at a predetermined acoustic frequency, together with signals of other acoustic frequencies adapted to confuse the first mentioned signals, a radio transmitting apparatus operated under the control of the signaling sound record and tuned receiving apparatus to respond only to the first mentioned signals.

4. In a radio signaling system a radio transmitter adapted to send impulses of acoustic frequency and a single sound recording apparatus adapted to control the said radio transmitter, which sound recordmg apparatus has impressed upon it a succession of signals of other predetermined acoustic frequencies adapted to mask the aforesaid succession of signals.

5. In a system orradio signaling control p employing acoustic frequencies, a radio re- 1 by .the radio. receiving" apparatus,

acoustic receiver tunedto respond only to a celving apparatus, a sound emitter operated an predetermined signaling frequency, an electricalcircuit controlled by the said acoustic receiver and an oscillatory. inertia member having a natural low period of swing under transmitting a regularly timed 'succession of I sign aling impulses at predetermined acoustic frequency, a radio. receiver, an

emitter adapted to be operated by the said radio receiver, an acoustic receiver tuned to I respond only to the signaling acoustic frethe controlling signals, whereby the inertia quency, an electrical circuit operated by said acoustic receiver and an oscillatory inertia member under the control of the said circuit, the natural period of swing of the said member corresponding to the timing of member may build up its oscillations by the successive timed impulses.

8. In a system of radio signaling control employing acoustic frequencles, a radio receiving apparatus, a sound emitter operated by the radio receiving apparatus, an acoustic receiver tuned to respond only to a prede termined signaling frequency, an electrical circuit controlled by the'said' acoustic receiver, a wheel mounted to oscillate under spring control with a natural low period of swing, and means whereby the said wheel may be given impulses by the said electrical circuit, which impulses cause the wheel to oscillate and to build up its oscillations. I

9. ha system as claimed in claim 8, an

electrical clrcuit under the control of the oscillating wheel and a control device inthe' said circuit operated by the wheel when the oscillations of the latter attain: apredetermined. amplitude.

10. In a radio signaling system, a radio transmitter adapted to send signals of acoustic frequency and means for automatically producing a timed succession of signaling impulses at the transmitter having a predetermined acoustic frequency, to-

gether with signaling'impulses of other frequencies adapted to mask the aforesaid succession of s1gnaling impulses, a radio receiving circuit, 'a second emitting device under the control of the said receiving cir cuit, a sound receiver-tuned to the acoustic frequency of the first mentioned-Si aling impulses, anelectrical circuit under-t e con- 1 trol of thesaid sound receiver an oscillatory inertia member and means whereby the said sound controlled electrical circuit 'im-v presses successive impulses on the said in-, ertia member. j

11; In a radio signaling system, a radio transmitter adapted to send signals of acoustic fre uency,'means; by which a timed succession o operativesignals having a plurality of predetermined frequencies are transmitted, together with signaling im-L pulses of other requencies adapted to mask the aforesaid succession of operative signals, radio receiving apparatus, a sound emitting device under the control of the receiver, a plurality of sound receivers tuned to the plurality of frequencies of the aforesaid operative signals and corresponding electric'al circuits operated by'the said sound receivers, whereby only those fre uencies employed for the operative signa s are efiec tive for their respective electrical circuits and oscillatory inertia member adapted to be actuated by the said electrical circuits as operated by the timed successive signals.

' OYRIL PERCY RYAN. 

